Rollover question

We just performed a test rollover including super/sub packages and we got the expected unseated line-items.  Those are easy enough to deal with - manually seat, etc.
 
The more unusual thing is that, even after making sure the "Add to orders created after" dates were set up properly, some orders combined nicely while other constituents ended up with rollover orders with a few series in each order.  I'm digging to find why, but any likely answers as to why certain orders would not combine as we would expect them to?

Your help is appreciated.

Brian Seitz
Center for the Performing Arts, Carmel IN